TODO

Current status

• Core parser tests: 302/302 on both JavaScript and Wasm.
• CommonMark HTML conformance: 652/652 with no skipped examples.
• Public JavaScript API CommonMark conformance: 652/652 with { autolink: false, tagfilter: false }.
• Markdown serialization parity with remark: 464 active examples and 78 skipped examples.
• CommonMark semantic round-trip: 611/652; 41 examples still change rendered HTML after normalization.
• GFM extension serialization comparison: 23 active examples and 1 intentional skipped example.
• Official GFM HTML conformance: 24/24 on both JavaScript and Wasm.
• A native mmmd implementation is available under src/cmd/mmmd-native.
• The only open GitHub issue is #1; its implementation is present locally but the issue remains open pending release/closure.
• The strict argument remains for compatibility; parsing is always CommonMark-conformant.

P0: Completed

• Gate GFM behavior against the official cmark-gfm HTML for all 24 extension examples on JavaScript and Wasm.
• Implement GFM disallowed-raw-HTML tag filtering for block and inline HTML.
• Keep GFM table bodies open for pipe-less continuation rows until a blank line or a new block begins.
• Implement GFM extended autolinks, including boundary, host, punctuation, entity, and balanced-parenthesis rules.
• Add a native CLI for issue #1. Native TUI output deliberately leaves Mermaid as an ordinary fenced code block because the diagram renderer is JavaScript/Wasm-only.
• Define serialize as a stable normalized format: ATX headings, canonical markers and spacing, a trailing reference-definition section, preserved reference styles, and idempotent/semantic round-trip tests.

P1: Correctness and maintenance

• Fix the 41 CommonMark semantic round-trip cases classified in docs/serializer-compat.md; prioritize block/list structure, block-start escaping, and reference definitions.
• Decide whether the 47 formatting-only remark differences are worth matching. They do not change rendered HTML and often conflict with the normalized serializer contract.
• Decide whether the experimental notebook package remains in this repository. Its separate backlog is in src/x/notebook/TODO.md.

P1: Performance

• Establish stable serializer and large-table baselines before optimizing them. The old percentage-regression notes were not backed by the current benchmark baseline.
• Keep just bench-simd as the regression gate for line scanning and long HTML terminator searches.

Completed or removed

• Full CommonMark HTML conformance, including nested lists, setext headings, emphasis, and reference-link resolution.
• Split block parsing into focused files.
• SIMD line scanning and HTML terminator search benchmarks.
• Official GFM HTML conformance, tagfilter, table continuation, and extended autolinks.
• Escaped pipes inside table inline elements (issue #6, including official GFM example 200).
• Native mmmd CLI with a deterministic Mermaid fallback.
• Stable normalized serializer contract and canonical reference definitions.
• GitHub alert blocks and complete footnote rendering with repeated back references.
• Display-math blocks with a replaceable trusted-HTML renderer boundary for KaTeX-style integrations.
• Container/text directives, definition lists, and standalone block attributes.
• Shift nested ordered/unordered list-item and child-block spans during incremental reuse.
• Resolve 5 of 6 GFM serializer differences. Keep example 204 intentionally different because remark exposes an overflow cell that official GFM ignores.
• Remove the experimental Folddown package, public API, viewer, workflow, and documentation.